Characterizing the outlines of degraded fine-particles by fractal dimension.

Fractal dimension has been used extensively as a descriptor of the rugged outlines of fine-particles. Potentially, it may be a useful parameter for characterizing the outlines of fine-particles which have been subjected to some form of chemical degradation. Here, fractal dimension values have been computed for the outlines of microscopic lead fine-particles both before and after weak hydrochloric acid dissolution experiments. Values obtained for the post-dissolution rugged profiles were greater than those of the pristine fracture grains which had a Euclidean form. The profiles of the degraded fine-particles could be characterized by a single fractal dimension value, or they exhibited multifractal behavior. Data from profiles of fine-particles lead from the natural environment of the soil suggest that fractal dimension calculations may provide a useful descriptor for particles which have undergone chemical dissolution and transformation in such an environment.